Generally, the cores for sporting balls, such as baseballs or softballs, etc. have a solid center for absorbing the force while being hit with a bat during game use. Furthermore the ball must have sufficient elasticity. The center or core of the ball must be produced with a soft or solid material and a two piece cover material is stitched over the core.
Referring to FIG. 9 in stitching the ball, a core is placed with two pieces of cover panels 11 so as to form a half-finished sporting ball 1. The half-finished sporting ball is placed on a clamping tool 2 of a ball stitching table. The clamping tool 2 generally includes a clamping head 21 and an elastic clamping unit (not shown) below the clamping head 21. A diameter of the clamping tool 2 is smaller than the half-finished sporting ball 1 so that the half-finished sporting ball 1 can be retained in the clamping head 21. Then by elasticity, the clamping head 21 can expand elastically. Thereby the clamping tool 2 can retained the half-finished sporting ball. Then the 2 pieces of cover panels 11 are stitched.
To stitch the two cover panels over the core requires strong pulling force and lengthy training period for workers. However the hard stitching work and lengthy training period makes it less desirable to attract new workers. Furthermore the work process is slow and the production rate is also low. Thus there is an eager demand for a novel ball stitching machine which requires less hard work for workers, reduces training period time and increases productivity rate.